In a landmark public health finding, a new study from the Harvard School of Public Health finds that carbon dioxide (CO2) has a direct and negative impact on human cognition and decision-making. These impacts have been observed at CO2 levels that most Americans — and their children — are routinely exposed to today inside classrooms, offices, homes, planes, and cars.

The piece to which Gore is referring concerns a study by the Harvard School of Physical Health, which says that carbon dioxide (CO2) has a negative effect on cognitive abilities and decision-making.

According to the study, which tested participants in a controlled office environment under a range of conditions, an increase in CO2 intensity of 400 ppm (parts per million) can impair people’s cognitive scores by an average 21 per cent. Its biggest impacts were on Crisis Response, Information Usage and Strategy.

There were noticeable effects at CO2 concentrations of 950 ppm (about what you’d find in a typical office) and even bigger ones at 1400 ppm (quite common in, say, school classrooms). Current atmospheric CO2 concentrations are around 400 ppm.

Though the report was specifically about indoor environments, it has understandably been seized on by green activists with an interest in bolstering the ailing climate change scare narrative.

That’s why it has been written up enthusiastically by George Soros’s pet climate attack dog Joe Romm at the green propaganda site Think Progress. And why, of course, Al Gore is bigging it up on his Twitter feed.

It matters to them very much that carbon dioxide should be demonized in the run up to this December’s UN climate conference in Paris because, otherwise, people might be the under the impression that CO2 is in fact a benign trace gas which does far more good to the world than harm.

It is a proven fact that plants, including trees and all our food crops, are capable of growing much faster at higher levels of CO2 than present in the atmosphere today. Even at the today’s concentration of 400 ppm plants are relatively starved for nutrition. The optimum level of CO2 for plant growth is about 5 times higher, 2000 ppm, yet the alarmists warn it is already too high. They must be challenged every day by every person who knows the truth in this matter. CO2 is the giver of life and we should celebrate CO2 rather than denigrate it as is the fashion today.

We are witnessing the “Greening of the Earth” as higher levels of CO2, due to human emissions from the use of fossil fuels, promote increased growth of plants around the world. This has been confirmed by scientists with CSIRO in Australia, in Germany, and in North America. Only half of the CO2 we are emitting from the use of fossil fuels is showing up in the atmosphere. The balance is going somewhere else and the best science says most of it is going into an increase in global plant biomass. And what could be wrong with that, as forests and agricultural crops become more productive?

Naturally, the green movement needs to find a counter-argument to this heresy. So many vested interests are now embroiled in the campaign to “decarbonize” the global economy that it is far, far too late for them to row back now and admit that carbon dioxide isn’t the big problem the alarmists’ computer models predicted it would be.

That was one of the reasons the “ocean acidification” scare was invented: as a fallback position in case it were to become clear – as it increasingly has – that anthropogenic global warming theory is a busted flush.

And it’s why, of course, attempts will be made to use this new study as further evidence that CO2 is a hazardous pollutant.

If the study is indeed an accurate representation of the effects of CO2 on humans, though, it will come as a big surprise to the US navy submarine service, where CO2 concentrations frequently reach 8,000 ppm (20 times current atmospheric levels) with few observed adverse reactions. Yes, CO2 can cause headaches but normally these start at concentrations of 30,000 ppm; and at even higher concentrations it can be fatal. But submariners are capable of performing high level tasks efficiently at CO2 levels dramatically higher than the ones claimed to be a problem in the Harvard study.

Of course, if the study does prove to be accurate and CO2 really is making everyone more stupid than Al Gore has a lot of explaining to do. His carbon footprint is bigger than almost anyone’s, so you could argue that if the world is getting dumber, then Gore bears a significant chunk of responsibility for it.